Stock-Based Compensation - Assumptions (Details) - shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Valuation of Stock Option Grants to Employees
Expected volatility, minimum		55.00%
Minimum
Valuation of Stock Option Grants to Employees
Expected term (years)		5 years 3 months
Performance-based awards
Valuation of Stock Option Grants to Employees
Risk free interest rate, minimum	0.80%	0.54%
Risk free interest rate, maximum	1.52%	1.64%
Expected volatility, maximum	60.00%	65.00%
Performance-based awards \| Minimum
Valuation of Stock Option Grants to Employees
Expected term (years)	7 years 3 months
Performance-based awards \| Maximum
Valuation of Stock Option Grants to Employees
Expected term (years)	10 years	7 years 3 months
Employee and non-employee stock options
Stock Based Compensation
Options granted (in shares)	391,000
Employee stock options
Valuation of Stock Option Grants to Employees
Risk free interest rate, minimum	0.81%	0.31%	1.60%
Risk free interest rate, maximum	1.67%	1.70%	2.60%
Expected dividend yield	0.00%	0.00%	0.00%
Expected volatility, minimum	55.33%	49.94%	42.53%
Expected volatility, maximum	63.30%	61.96%	45.84%
Employee stock options \| Minimum
Valuation of Stock Option Grants to Employees
Expected term (years)	5 years 1 month 9 days	5 years 2 months 19 days	5 years 2 months 23 days
Employee stock options \| Maximum
Valuation of Stock Option Grants to Employees
Expected term (years)	10 years	10 years	10 years
Non-employee stock options
Stock Based Compensation
Options granted (in shares)	31,553
Options unvested (in shares)	730

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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No definition available.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Gross number of share options (or share units) granted during the period.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Publisher FASB
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- Definition

Number of non-vested options outstanding.

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